充分條件與必要條件教學(xué)課件

1.8.1充分條件與必要條件學(xué)習(xí)目標(biāo)：（1）正確理解充分條件、必要條件和充要條件的概念；

（2）能正確判斷是充分條件、必要條件還是充要條件；1.8.1充分條件與必要條件一、復(fù)習(xí)回顧：原命題若p則q

逆命題若q則p

否命題若p則q

逆否命題若q則p互

否

互逆互逆互

否

互為逆否互為逆否1、四種命題的關(guān)系2、四種命題之間的真假關(guān)系（1）原命題為真，（2）逆命題不一定為真，（3）否命題也不一定為真，（4）逆否命題一定為真。1.8.1充分條件與必要條件例1、判斷下列命題是真命題還是假命題：（1）若，則；（2）若，則；（5）若，則；（6）若方程有兩個(gè)不等的實(shí)數(shù)解，則．真真真假假假（3）全等三角形的面積相等；（4）對(duì)角線(xiàn)互相垂直的四邊形是菱形；二、新知識(shí)：1、推斷符號(hào)：的含義若p則q為真，記作若p則q為假，記作1.8.1充分條件與必要條件（1）若，則；真可記為：（2）若，則；假真（3）全等三角形的面積相等；假（4）對(duì)角線(xiàn)互相垂直的四邊形是菱形；兩三角形全等兩三角形面積相等可記為：（5）若，則；假（6）若方程有兩個(gè)不等的實(shí)數(shù)解，則．真可記為：有兩個(gè)不等的實(shí)數(shù)解可記為：可記為：四邊形的對(duì)角線(xiàn)相互垂直這個(gè)四邊形是菱形可記為：1.8.1充分條件與必要條件2、充分條件與必要條件：一般地，如果已知那么就說(shuō)，p是q的充分條件，q是p的必要條件．例如：的充分條件的必要條件兩三角形全等兩三角形面積相等兩三角形全等是兩三角形面積相等的充分條件．兩三角形面積相等是兩三角形全等的必要條件．注意：條件和結(jié)論是相對(duì)而言的，由于的等價(jià)命題是：即，若q不成立，則p就不成立，故q是p成立的必要條件，但必須注意q成立時(shí)，p可能成立，也可能不成立，即q成立不保證p一定成立。1.8.1充分條件與必要條件

例2

、指出下列各組命題中，p是q的什么條件，q是p的什么條件：（1）（2）p：三角形的三條邊相等；

q：三角形的三個(gè)角相等．解：（1）由于的充分條件的必要條件（2）三角形的三條邊相等三角形的三個(gè)角相等“三角形的三條邊相等”是“三角形的三個(gè)角相等”的充分條件．“三角形的三條邊相等”是“三角形的三個(gè)角相等”的必要條件1.8.1充分條件與必要條件3、充分性與必要性分類(lèi)：（3）既充分又必要要條件：即（1）充分不必要條件：即（2）必要不充分條件：即（4）即不充分又不必要條件：即4、充分性與必要性的判斷步驟：（1）認(rèn)清已知命題的條件和結(jié)論；（2）考察的真假。課堂小結(jié)：（1）正確理解充分條件、必要條件和充要條件的概念；

（2）能正確判斷是充分條件、必要條件還是充要條件；CreditRiskManagement

EnhancingYourBottomLineEbrahimShabudinManagingDirectorDeloitte&ToucheLLPTheAFP23rdAnnualConferenceNewOrleansNovember3-6,2002CreditBackgroundThoroughidentificationandaccuratemeasurementofcreditrisk,supportedbystrongriskmanagementcanhelpimprovethebottomline…..Anuncertainandvolatileeconomic environmentsignificantlyimpactsthisability…..Thedesiretogrowandturninoutstanding resultshasatendencytoputpressureonthe checksandbalanceswithinbusinessesValuePropositionCreditplaysacriticalrolein“selling”productsandservicesExpandsrevenueopportunitieswithcreditworthy,incrementalcustomersUtilizesinnovativestructurestosupportbusinessrelationshipsEffectivecreditriskmanagementlimitscreditlossesandprovidesstablecashflowsandearningsMarketplacerewardscompaniesexhibitingearningsandcashflowstabilitywithhigherP/EmultiplesMarketplacepenalizescreditinducedvolatilityand“surprises”RaisesquestionsaboutqualityofmanagementCorporateCreditRiskCompaniesareexposedtosignificantlevelsofcreditriskemanatingfromdifferentsourcesAccountsReceivablesOtherNotesReceivablesBuyerandFranchiseFinancingWithRecourseFinancingProjectFinanceStructuredTransactionsLeaseswithRecourseDerivativesExposuresFX,InterestRateRisk,Commoditiesetc.CollateralRiskParentorThirdPartyGuaranteesCommercialandStandbyLettersofCreditNotealsothatCriticalSupplierstothecompanymayposespecificcreditriskDSOImpact…anexampleActualCompanyAPeerAverageQ3A/R$295,396,000Q3Sales$261,201,000\DSOs=124*51.3HypotheticalDCashDSOs51.3Q3Sales$261,201,000\Q3A/R=$122,002,230+$173,393,770*Equals295.4M/261.2Mx90(ornumberofdaysinsalesperiod)CreditasaFacilitatorCreditriskmanagementisimportant

CreditisafacilitatorofbusinessgrowthandperformanceHighbusinessmarginstendtoattractlowerqualityclientsandthereforehigherriskprofiletomanageClients(buyers)maybeconcentratedinselectedindustriesandprovidelimitedportfoliodiversificationopportunityPoorcreditriskmanagementresultinginnegativeimpacttobottom-lineisheavilypenalizedbymarketsCreditStrategy&RiskToleranceSpecificQuantifiableObjectivesManagementReviewMethodologyCreditStrategyStatementandRiskToleranceCoordinationwithBusinessPlanThebusinessstrategiesandobjectivesdrivetheestablishmentofcreditpoliciesandprocedures.Measurementandreportingaswellastheuseofcurrenttechnologiesenhancecreditdecision-makingandimproveriskmanagement.Theentireprocessiscontinuallyre-evaluatedandimproved.CreditRiskAreastoConsiderCreditPolicyCreditApprovalAuthorityLimitSettingPricingTermsandConditionsDocumentation:ContractsandCovenantsCollateralandSecurityCollections,DelinquenciesandWorkoutsExposureManagementAggregationControlPeriodicAccountReviewsPayments/AgingCreditConditionCompliancewithCovenants,TermsTechnology/ReportsTransactions/BookingsRisk-adjustedReturnSalesChannelsRiskStrategyUnderwritingStandardsCreditApplicationAnalysisBusiness/IndustryFinancialCreditCreditScoringandRatingsOrigination/AssessmentAdministrationMonitoring/ControlRiskManagementPortfolioManagementConcentrationDiversificationAllowanceforBadDebtsRiskMitigationObjectivesTypeofExposureInstrumentsorMethodsValueCreationBusinessPerformanceMeasuresOrganizationsneedarigoroussetofmeasurestosupportcontinuousimprovementPerformance-basedmanagementutilizesmetricsthatmeasureactualperformanceagainstpredeterminedthresholds.Thethresholdsareestablishedtakingintoaccounttheorganization’sstrategy,operatingenvironmentandprocesscontrols.Themeasuresdrivevaluecreationandshouldsupportproblemidentificationandcorrection.BusinessStrategySystemsOperationsFinancePerformanceManagementSaleschannelsContracts&DocumentationCreditanalysisCreditlimitPricing&termsCreditAnalysisCreditDecisionsCollectionsCREDITPOLICYCollateralacceptancePortfoliomanagementFinancialanalysisDisposal/

RiskmitigationCollateralmanagementCustomermanagementExposuremeasurementManagementreportingExposureaggregationRecoveriesCreditscoringRiskratingRISKMANAGEMENTCreditRiskManagement’sInter-relatedActivitiesComplianceOriginationReportingTransactionsCreditPolicies

&Procedures

Analysis&RiskManagementGovernance,ControlandImplementation

MeasurementMethodologiesTechnology&DataIntegrityCreditStrategy&RiskTolerance

AcompleteandcoherentriskmanagementframeworkcontainsthefollowingelementsCreditRiskManagementANewParadigmAnewbusinessparadigmhadevolved:causingalackofrelianceongoodfundamentalanalysisTheideathatstockmarketvalueswouldcontinuetogoupindefinitelyIncreasinglycompetitive,complexandvolatilemarketplaceHigherthanexpectedactualdebtburdensExtensiverelianceonunrealisticfuturecashflowsFailuresincorporategovernanceQuestionablepersonalandcorporateethicsImplicationsforCorporateGovernanceCurrentorganizationstructurestoberevisitedClarityaroundrolesandresponsibilitiesNeedforhonesty,integrityandindependence(self-regulation)TechnicalexpertiseofpeopleandstrongmanagementprocessesImproveddisclosurerequirementsImportanceandimplementationofsanctionsIncreasedlegislationandcompliancerequirementsFoundation:CreditRatingandUnderwritingStandardsRiskIdentification,Origination,CreditAdministration,etc.ShortTerm:ManagingExpectedLossRiskIdentification,Transaction

Structuring,Approval&PricingDecisions,Reserving,etc.NearTerm:ManagingEconomicCapital/CreditVaRPortfolioRiskConcentration,RiskBasedLimits,etc.

Vision: ManagingRisk/ReturnPricingdecisions,Performancemeasurement,businessandcustomersegmentation,compensation,etc.AbusinessmodelviewofCreditRiskInfrastructurecomponentsCreditRiskManagement–StrategicVisionDevelopmentStagesFoundationStageincludesapplicationofriskidentificationmethodologies,riskscoringorratingsystemsandstrongunderwritingstandards

BasicStagetendstoincludemanagingonatransactionalbasisbyevaluatingspecificattributessuchasstructuring,collateralandpricing

AdvancedStagerepresentsmanagingonaportfoliobasisincludingaspectssuchasconcentrations,correlationsanddiversification

TheSophisticatedStageincludesapplicationofhighlydevelopedmeasurementtechniquesfortransactionsandportfolios,supportedbydecision-makingrelatingtosegmentsorbusinessesagainstestablishedhurdlerates.CreditRiskClarified

Creditriskisdefinedastheriskoflossorpotentiallossresultingfrom:DefaultincontractualobligationsbyacustomerMigrationinconditionandratingDeteriorationinperformance

Creditriskincludesbothanexpected(predictable)andunexpected(volatile)losscomponent.

BusinesseshavetocontendwithExpectedandUnexpectedLossesExpectedLossesAnticipatedCostofdoingbusinessChargedtoprovisionsCapturedinpricingRelativelyeasiertomeasureAssessingexpectedlossincludesdeterminingexposure,defaultprobabilityandseverityUnexpectedLossesUnanticipatedbutinevitableMustbeplannedforCoveredbyreservesAllocatedtobusinessesDifficulttomeasureAssessingunexpectedlossrequiresmakingqualitativejudgmentsaroundpotentialvolatilityofaveragelossesCreditRiskManagementExplainedAlthoughcreditriskmaybedifficulttomeasureitisimportanttoestimateandmanage

WhatdoesCreditRiskManagementmean?Itrepresentsaninstitution’sabilitytoproperlyidentifyandevaluatethepotentialriskofdefaultinpaymentofobligationsofcustomersItincorporatesthefirm’sabilitytoeffectivelymanageandcontrolthisexposureinawaythatisconsistentwiththeinstitution’sbusinessstrategy,riskappetiteandcreditcultureImportantBuildingBlocksEffectiveCreditRiskManagementrequiresClearoriginationandunderwritingstandardsAstrongcorporateandcreditcultureHighlydevelopedriskmeasurementtechniquesAbilitytorecognizeandcoverexpectedandunexpectedlossesPricingcommensuratewithrisksundertakenMethodologiestoassessnetprofitcontributionsbycustomersandappropriatebusinesssegmentsProperallocationofcapitalandmanagementresourcesInorderto:Improveoverallcorporateperformance,measuredbyahigherEPSorP/Eratio(ormarketvalue)CreditPolicyandProcessCreditPolicyshouldbeclearandconciseCreditUnderwritingStandardsmustbedevelopedandincludedinpolicyCreditProcessesshouldbereasonableandallowquickresponsetoclientsHealthybalancebetweensalesandcreditapprovalshouldexistandberespectedRiskMonitoringExposuremustbecompleteandcurrentRegularreportingandupdatingofclients’paymentperformanceMinimumannualreviewsofclientsshouldbeperformedFinancialconditionsshouldberegularlyassessedRequiredactionmustbeinitiatedandfollowupmusttakeplaceContractTermsandDocumentationContractnegotiationsmusttakeplaceattherightlevelintheorganizationAppropriateapprovalsmustbeobtainedInternalorexternallegaldepartmentsmustdocumentcompletelyTermsandconditionsshouldbeunderstoodandcompliancemechanismputinplaceExceptionsmustbereportedandmanagedurgentlytoresolutionRiskRatingSystemEffectivenessCreditScoringisgenerallyusedto“riskrate”homogeneousportfoliosHighestapplicabilityisinconsumerandretailportfoliosSomeadvancedscoringsystemsarebeingmigratedforuseinrating“middlemarket”clientsSuchmodelsareonlyasgoodastheunderlyingassumptions InternalcreditratingsystemsaredifficulttoassessandareoftennotindependentlyvalidatedClientrelationshipmayinterferewithobjectiveassessmentofrisksRatingcriteriausuallyamatterofpracticeratherthanwrittenpolicyRatingsarenotconsistentovertimeQualitativecreditassessmentsoftenlagcurrentmarketinformationInstitutionsoftenassume

amappingwithexternalratingsinordertoquantifycreditriskEffectiveRiskRatingSystemsSufficientgranularityofriskratingcategoriesAccurateandtimelyassignmentofratings

ClearandconsistentapplicationofdefaultdefinitionPeriodiccalibration,triangulationandvalidationofriskratingsAccurateidentificationofmigrationoftransactionsandportfolios(asreflectedbyupgradesanddowngradesinratings)CreditEvaluation:FinancialFactorsGettheinformationyouneedtomakeafullanalysisSomeinformationwillneedtobecross-checkedandobtainedonaregularandtimelybasisBeconstructivelycynical:newbusinessmodelsaredifficulttopulloffBecognizantofdelayingtacticsNumbersdon’ttellthewholestory!CreditEvaluation:QualitativeFactorsEvaluationofsubjectivefactorsisoftentimesmoreimportantthanthenumericalanalysisPeoplemakeabusiness:visions,valuesandstrategiesareonlywordsunlesspeopleimplementthemManagement,industry,product,geography,competitionetc.allinfluenceresultsandmustbeproperlyassessedAnalysis-paralysismayleadtowrongdecisionsArtandScienceofJudgmentGettingaccesstothebestclientsandalltherelevantinformationisachallengeEnsuringproperanalysisisdonerequiresastrongcorporatecultureUtilizingqualifiedresourcesbothinternallyandexternallyenhancestheresultsOftenthelackofthewilltoactiswhatcauseshighlossesConcludingCommentsCompaniesthatmeasureandmanagecreditriskinapro-activemannerwillbenefitfromafavorableriskprofileresultinginHigherrevenueLowerlossesImprovedefficienciesHigherEPS,P/EratiosandmarketvaluesConcludingCommentsRiskAssessmentandLimitManagementCreditInfrastructureandPortfolioManagementCreditAnalyticsSupportCreditTechnologyEnablementCreditQualityCreditUnderwritingRiskRatingSystemEffectivenessCounterpartyandPortfolioLimitsOrganizationalStructurePoliciesandProceduresTechnologySelectionandImplementationProblemAssetManagementRiskRatingCalibrationTransactionPricing,StructureandSupportDefaultProbabilityandRecoveryCalibrationCreditReserveMethodologyRiskBasedPricingModelsRiskAdjustedReturnAnalysisPortfolioValueMeasurementCreditRiskMeasurementCreditPerformanceScorecards

InternalSoftware

ExternalVendorSoftwareAppendix:BusinessProposalChecklistBusinessProposalSummaryCustomer,Rating,LegalStatus,LineofBusinessGuarantor,ifany…sameCollateral,ifany…truevalueexplainedOtherSupport,ifany...LegalormoralonlyTheTransaction…risksandmitigationAmount,purpose,termsandconditionsSourcesofrepayment…clearlyidentifiedClientpaymenthistoryandrelationshipAppendix:BusinessProposalChecklistRationaleandAnalysisCustomer,Guarantor,Collateral,SupportFacilityDescriptionAmount,purpose,tenor,pricing,terms,conditions,covenants,restrictionsetc.Consideraffectonabovee.g.newleverageFacilityRating?RepaymentCapacityFuturecashflow,conversionofassetsetc.Consi